This invention relates to apparatus for cleansing the interior of a tank and particularly, but not exclusively, apparatus for cleansing the interior of a tank of a bulk transporter tanker vehicle, such as a road haulage tanker vehicle for the transporting of milk or other liquids.
Such tanks are usually provided with an access hole (manhole) and are cleaned by spraying a liquid, such as water, into the tank by means of a hose. The cleaning operation is usually messy, involves a long time period and does not always clean the interior of the tank satisfactorily.
Spraying apparatus is known in which spray arms are bodily rotated through 360 degrees about an axis at a right angle to a vertical axis.
A disadvantage of the known apparatus is that material dislodged from the surface of the tank by the liquid sprayed from the rotating spray arms tends to be carried by the spray onto the already cleaned surface and again contaminates the surface.